I'm Michelle Franzen and New York as the financial markets closed. On this -- -- -- this is doing its job today were looking at a sudden rise for Allergan. A pharmaceutical company specializing in drugs to treat -- conditions and also happens to be the manufacturer of a little thing called Botox. I'm joined now by -- -- from Yahoo! finance like there's an offer on the table for -- again. That's raising some eyebrows despite all that Botox what's going on. Sure is yes 45 billion dollar offer came out very late yesterday in the market reacted positively to a driving out -- in shares up. What's interesting about the proposed deal is that it is bill -- man whose prominent activist hedge fund manager kind of fixed targets among companies and tries to get them to do what he wanted to do. Teaming up with another pharmaceutical company called -- -- they -- both bought. It through a -- they both fought close to 10% of Allergan shares and then they come -- publicly say. Where you want value to buyout and into it almost seems have act meant. Is managing to play. Both sides -- this potential deal the market reacting positively pushing -- -- stock up as well as value basically thinking there could be. You know kind of good long term value -- such a combination. But it also is is sort of a unique structure to a deal in terms of having the the sort of very instrumental role actress and activist investor at the center. They certainly mention that investors liked what they heard possibly happening let's take a look at Allergan stock at the two day chart here give us an idea of -- look at. Well what's interesting you saw them -- major pop today that -- second actually been climbing kind of relentlessly if quietly before this because -- -- was very busily. Buying up stock. And so it's it's not been exactly a bargain bin situation in terms of Allergan shares they've actually been very good performers the business itself is doing very well Botox. It's a long term growth story for better -- for worse not just for cosmetic purposes but for other. Kind of pharmaceutical therapeutic uses so it does seem as if you know the market is celebrating. This instance and also the general idea of companies being put in play in this mapped out a press release -- Allergan says it's looking at the offer but -- stockholder Texas sit tight. For the time being they said any indications with the board might decide yeah. No there really isn't a clear indication it's kind of a standard statement that the board might issue when -- -- the subject of of the top of a takeover offer. They will have to consider -- a duty to do so it actually consider this deal. And it does seem as if we you know whether they go along with the deal at this price had potentially higher priced had to renegotiate the terms or anything like that. It does seem as if it's going to. One way or another make out -- get a potential target if this deal falls apart. I do think others might step in and say you know lots of deal making going on health care in general. Maybe this is a prize it won't be there very long so one way or another I think out means boards gonna have to consider whether it wants to to -- independent. And Allergan of course also -- pretty savvy company its CEO of course. Doing those tests and making Botox what it is today. Is this offer though this sort of semis sort of -- were coming after you. Yes opportunity. Is -- something that just comes around once or company like this. It's just not clear I mean I think this particular type of deal -- it certainly unique at the moment may be still be copycats down the road. I don't think it's now or never for Allegheny necessarily in terms of doing this. As -- said their business itself is doing well -- at a size where they could certainly go it alone if they choose. But you have a lot of upset investors right now they say when walking away from a deal we have no plan B. -- that might actually take -- in the air out of out of the stock at this point. And I even if they can say look Botox has always wonderful use as long term. We have other products in the pipeline it probably wouldn't in the short term satisfy Wall Street. And then you know what is alaskans -- And then what are they specifically offering here is undervalued. I wouldn't say it's undervalued I'd say the value comes in that kind of uniqueness of the property mean because this set of products. Is you know considered to be so special by people in the industry and one of the reasons is -- you know as they say we're only sort of they believe they're only sort of god kind of going to -- below the surface barely -- -- Botox can do it's also being prescribed for migraines for incontinence exactly it basically they think they'll tell you. It's useful in any instance where you want to incapacitate the target -- a group of cells but do something that you don't want them to -- so. Theoretically very broad application and they do have many other products -- -- Botox. So they can kind of make a go of it on their own but does -- say in this instance right now in terms of the chess match it's going -- I do think they're gonna have to say you know we want this deal will negotiate potentially for a higher price will throw it open as an auction to see if anybody else wants to pay more for. It's very good we'll keep an eye on that Mike -- toll of Yahoo! finance thanks for joining us. Thank you even watching stories stocks stay with abcnews.com for your latest headlines I'm Michelle Franzen in New York.

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